System of transmitting images



March 1, 1938. v w MCKAY 2,109,622

SYSTEM OF mmsmnwme iMAGES 2 Sheets-Sheet 1 Original Filed Feb. 6, 1933 INV ENTOR Jv/m/ M "(KAY March 1, 1938. J. w. M KAY SYSTEM OF TRANSMITTING IMAGES Original Filed Feb. 6, 1953 2 Sheets-Sheet 2 T w m w M W59 v W "2.1; 2 L .W .6 9 zm a 9%. M H a 2/ L 1 a m e "a w 5 9 f. E g

Patented Mar. 1, 1938 2,109,622 SYSTEM OF TRANSMITTING HWAGES John W. McKay,

Brooklyn, N.

Y., assignor to National Television Corporation, Wilmington,

., a corporation of Delaware Original application February v6, 1933, Serial No. now Patent No. 2,056,974, dated October 13, 1936. Divided and this application September 12, 1935, Serial No. 40,271

7 Claims.

This invention relates to a system of transmitting images from one place to another by scanarrangement showing the controlling means thereof;

Fig. 4 is a front sectional view of the disc taken on the line 4 4 of Fig. 3; and

Fig. 5 is. a top sectional view of the sleeve for moving the relative position of the discs taken on the line 5-5 of Fig. 3.

This applicati a cabinet 262. The disc 254 comprises an opaque disc of metal or other opaque material and is provided with a plurality of holes 263 (Figs. 1

width of the picture.

Such a disc rotating at the proper speed in H front of the light 260 area on the illuminated electrode of the lamp equal to the size of the picture to be received, and as the light is mo the incoming television signal the picture appears on the edge of the disc. For a sixty line picture there are necessarily sixty of the holes 263. If it is desired, however, to make the appa- Each of the vided with a small fingers 266 is, however, prohole 261 which is normally it is desired to shift to the one hundred and twenty line picture, the disc 265 is rotated slightly counterclockwise with respect to the disc 254 with the result that the fingers 268 each cover one of the holes 263 thereby exposing the holes 264 as is clearly indicated in Fig. 2. That portion of each of the fingers 269 which contains the hole 261 will then fall directly over one of the holes 263, thereby cutting down the size of the hole 263 to that of the holes 264, the holes 261 in the fingers 266 being exactly the same size as the holes 284.

It will thus be seen that when the discs are in the position shown in Fig. 1, sixty holes will be arranged in the disc for scanning, but when the second disc 265 is moved to the position indicated in Fig. 2, there will be one hundred and twenty holes equally spaced and of the same diameter. It will, however, be evident that the height of the picture which is determined by the radial distance between the outermost and innermost hole will remain the same for both the sixty line and one hundred and twenty line picture, while the width of the one hundred and twenty line picture will be half that of the sixty line picture. This alteration in the proportion of the received image is compensated for by a cylindrical lens (to be later described), which is automatically moved between the disc and the observer and tends to widen the picture to its proper dimension.

In Fig. 3 is shown the mechanism for moving the disc 295 with respect to the disc 264. Tothis end a sleeve 25% is rotatably mounted upon the sleeve 251 and is provided with which the disc 255 is attached. The sleeve 268 may be held against axial movement on the sleeve 251 by means of a washer 219 which in turn is held by a nut 211 threaded on the reduced end 212 of the sleeve. The sleeve 298 is provided with a pair of grooves 213 which are curved so that one end is ofiset from the other as shown in Fig. 5. The sleeve 251 is also provided with a pair of grooves 214 which are parallel to the axis of the sleeve and align with one end of the grooves 213 when the discs are in their sixty line picture position and with the other end of the grooves 213 when the discs are in their one hundred and twenty line picture position. A pair of pins 215 extend through the grooves on each side of the shaft and are mounted in a ring 218 which rotates in a ball race 211, mounted in a sleeve 218 against a flange 219 on one side and secured by a ring 289 on the other, threaded into the end of the sleeve.

The ring 216 with its pins is free to rotate with the scanning element, but upon axial movement thereof, the pins slide in the grooves 213 and 21s and cause the slight rotation of the disc 265 with respect to the disc 254 necessary to change from a sixty line picture to a one hundred and twenty line picture.

Axial movement of the ring 219 and associated parts is accomplished by moving the sleeve 218 axially. This is done by mounting the sleeve 218 for axial movement in a tubular member 28! to which it is keyed by the key 282 to prevent rotation therein. The sleeve is provided with an end closure 283 in which is a tapped hole 284 adapted to receive the threaded end of a shaft 285, the other end of which is mounted for rotation in a bearing 289 in the end 281 of the tubular member 281. This end is secured against the front wall of the cabinet and the shaft extends through an opening 288 and is provided with a knob 28.9 on the outside for manual manipulation. A. pair of collars 2953 and 29! are provided attached to the shaft on the outside and inside of the end wall 291 of the tubular member 28! so as to prevent axial movement of the shaft 285.

Rotation of the knob will cause the shaft to be directed into or out of the end plate 283 of the sleeve 218 and thereby cause the sleeve to move backward and forward depending on which way the knob is rotated. This will move the ring 216 and associated pins axially which will cause the relative movement between the discs 254 and 295 as already described. The shifting of the discs may thus be accomplished independently of the rotation thereof.

In order to compensate for the difference in width of the picture for a one hundred and twenty line picture as compared to a sixty line picture, I provide a cylindrical lens 292 which is mounted in a movable arm 293 attached to a sleeve 294. The sleeve 284- fits around the tubular member 28| and is held against a rib 295 formed on the tubular member by a ring nut 2% which is screwed onto the threaded end of the member. Thus mounted the arm 293 can oscillate about the tubular member, throwing the lens 292 into and out of position in front of the viewing lens 26!. oscillate the arm 293 I provide a small pinion 291 on the shaft 285 which meshes with an idler gear 298 rotatably mounted on a lug 299 attached to the inside of the tubular member 28! by means of a pin 389. The gear 298 has its upper edge extending through an opening 301 provided for that purpose in the upper edge of the tubular member 28 l, and meshes with rack teeth 302 provided on the inner end of the sleeve 294. The operator, therefore, has only to turn the knob 239 in order to shift both the lens and the discs to change from a sixty line picture to a one hundred and twenty line picture, and this change may be made regardless of the speed of the apparatus.

While the lens 292 has been shown as a cylindrical lens adapted to alter the image vertically and thus cut down its height, it is evident that a concave cylindrical lens might be used to increase the width of the image so as to make it the same size for either picture.

From all the above description, it is evident that I have provided a scanning apparatus for television in which the number of lines per picture may be altered and such alteration may be made while the machine is in motion so that it is possible to change from one system to another providing the apparatus is designed for those particular systems. While in the arrangement shown two systems only are usable, it is evident that the apparatus may be designed to accommodate more than two systems by suitable changes in construction of the apparatus.

Where the number of pictures per second sent out by the transmitting station is the same for systems of different numbers of lines per picture the speed of the motor will be the same. However, it is obvious that if one system has a different number of pictures per second the speed of the scanning element will have to be altered. This may be done by using a motor having different synchronous speeds or by arranging suitable change speed gearing so that the speed of the scanning element may be set for the desired number of pictures per second.

The apparatus has been described in connection with receiving television apparatus but it is obvious to those skilled in the art that the same devices are adaptable to transmittingtelevision apparatus by the substitution of a light sensitive cell for the modulated light used orthe substitution of a bright constant source of light for the modulated light while a bank of light-sensitive cells is positioned around the subject whose picture is being transmitted. It is, therefore, thought unnecessary to show a transmitting apparatus as theparts are essentially the same, and the invention is intended to cover both transmitting and receiving devices.

Many modifications may be made in the structure shown and described without departing from the spirit of the invention, and I do not, therefore, desire to limit myself to what has been shown and described except as such limitations occur in the appended claims.

What I desire to secure by Letters Patent and claim is:

l. A television apparatus comprising a scanning disc, a plurality of spaced apart apertures around the circumference of said disc in the form of a spiral, a plurality of smaller diameter apertures equally spaced around said disc on the same spiral line as said first apertures, there being one of said second apertures between every two of said first apertures, and means to alternatively block off said second apertures or uncover said second apertures and reduce the diameter of said first apertures.

2. A television apparatus comprising a scanning disc, a plurality of equally spaced apertures around the circumference of said disc in a spiral, a plurality of smaller diameter apertures also equally spaced around the circumference of said disc on the same line as said first apertures, there being one of said second apertiu'es between every two of said first apertures, a second disc positioned in juxtaposition to said first disc and having a spirally cut edge coming within the line formed by said apertures on said first disc, a plurality of fingers extending outwardly from the edge of said second disc, said fingers being spaced apart the same distance as said first series of apertures, an opening in each of said fingers equal in size to said apertures, and means toalternatively rotate said second disc through a slight angle with respect to said first disc whereby said fingers either cover said second series of apertures or cover said first series of apertures with the openings in said fingers in a line with said first mentioned apertures.

3. A television apparatus comprising a scanning disc, a plurality of equally spaced apertures around the circumference of said disc in the form of a spiral, a plurality of smaller diameter openings also equally spaced around said disc on the same line as said first mentioned apertures, there being one of said second apertures between every two of said first mentioned apertures, a second disc in juxtaposition to said first disc and rotatably mounted with respect thereto, said second disc having an edge which conforms to the spiral of said apertures but is less in diameter than said spiral, a plurality of fingers extending outwardly from the edge of said second disc, said fingers being equally spaced apart on the edge thereof with the spacing similar to the spacing of said first mentioned apertures, a hole in each of said fingers equal in size to said second mentioned apertures, means to alternatively move said second disc with respect tosaid first disc so that said fingers either cover said second apertures with portions of said disc covering the openings in said fingers, or said fingers cover said first apertures with the openings therein in aline with vsaid first apertures, and optical means to compensate for the difference in width between the scanned image scanned by said first apertures alone and by said first and second apertures together. a v

4. A scanning device comprising a scanning disc, a plurality of apertures in said disc arranged in a spiral to scan with a predetermined number of lines per picture, a second set of scanning apertures in said disc arranged to cooperate with said first set to scan said picture with a different number of lines per picture, means to cover said second set of apertures when the device is used for scanning at said first mentioned number of lines per picture, means cooperating with said last mentioned means to decrease the size of said first mentioned scanning apertures when said second mentioned apertures are uncovered, a member rigidly secured to said first mentioned scanning disc, a second member rigidly secured to said second mentioned disc, a groove in said first member, a groove in said second member, a pin adapted to engage the grooves of both of said members, and means to move said pin while said discs are rotating, said grooves being so arranged that movement of said pin will cause said members to rotate with respect to each other.

5. In a device of the class described a scanning disc, means on said disc to intercept and control light directed against said disc so as to scan a field with a number of lines, a second scanning disc mounted adjacent said said second disc adapted to cooperate with the means on said first disc to change the effective number of said first-mentioned means so as to change the number of scanned lines when said discs are rotated through a slight angle with respect to each other, a member having a slot therein attached to said first disc, a second member having a slot therein attached to said second disc, .9, pin adapted to engage both of said slots, and means to move said pin in said slots while said discs are rotated, said slots being so arranged that movement of said pin therein will cause relative movement of said members.

6. A scanning device comprising a pair of closely positioned scanning discs, one of said discs having means to intercept and control light directed against said disc so discs adapted to cooperate with said first-mentioned means to alter the effective number of said first-mentioned means and change the number of scanning lines when said discs are rotated through a slight angle with respect to each other, a shaft, means to secure one of said discs togsaid shaft, a sleeve attached to said means and having a groove therein extending longitudinally of said shaft, a second sleeve mounted rotatably on said first sleeve and secured to said second disc, said second sleeve having a groove therein extending longitudinally of said shaft, the slots in said sleeve being inclined at a slight angle with respect to each other, a pin engaging the slots in both of said sleeves, a ring surrounding said sleeves and rotatably mounted with respect thereto, said pin being rigidly attached to said ring, and means to move said ring and pin longitudinally of said sleeves while said discs are rotating whereby the movement of said pin in said slots changes the relative rotation of said discs.

7. A scanning apparatus comprising a pair of closely positioned scanning discs, one of said discs having means to intercept and control light disleeve and rigidly secured to said second disc, each of said sleeves having a longitudinal groove therein which is slightly inclined with respect to the other, a hollow member surrounding said sleeves, a bearing in said member, a ring rotatably mounted in said bearing, a pin mounted in said ring and engaging both of said slots, and means to manually adjust said hollow member longitudinally of said shaft.

JOHN W. MCKAY. m 

